Project Summary The prevalence of Alzheimer's Disease (AD) and other dementias is steadily climbing and predicted to affect as many as 16 million Americans by 2050. In 2016, 59% of dementia caregivers reported experiencing high levels of emotional and physical stress, and the risk that the chronic stress of dementia caregiving places on caregivers for developing a range of physical and mental health issues is extensively documented. Furthermore, caregiving burden has a deleterious impact on caregiving quality and quality of life in the care recipient. Interventions for dementia caregivers have primarily focused on reducing negative emotions and burden. However, over the past few decades, it has become clear that positive emotions are uniquely related to better psychological and physical well-being, independent of the effects of negative emotion suggesting that an intervention that specifically targets positive emotion holds promise for improving caregiver well-being and, ultimately, quality of care for the individual living with AD. Our recent randomized trial of the positive emotion skills intervention, delivered by trained facilitators via the web in N = 170 family caregivers of people with dementia resulted in significant improvements in caregiver psychological well being. However, facilitator- delivered interventions are costly and difficult to implement with fidelity on a large scale. Thus, we propose to take the next step toward widespread implementation of the LEAF intervention by conducting a 3-arm technology-based randomized controlled trial (N = 500) in which family caregivers of patients with Alzheimer's Disease (AD) are randomized to 1) the LEAF intervention facilitated remotely via web (N = 200), 2) the LEAF intervention self-guided online (N = 200), or 3) an emotion reporting control (N = 100) which will then cross over to the intervention after approximately 6 months, half to the facilitated arm and half to the self-guided arm. Our Specific Aims are to: 1) Compare the effect of web-based self-guided and facilitator- guided LEAF positive emotion intervention to an emotion reporting control condition on AD caregiver well- being (positive emotion, depression, anxiety, and perceived stress). 2) Explore effects of LEAF on caregiving burden, caregiving self efficacy, positive aspects of caregiving, quality of care, and AD patient quality of life and assess whether effects on these outcomes are mediated by improvements in positive emotion or other aspects of caregiver well being, and 3) Test whether caregiver age or gender, or patient dementia severity moderate the effects of the intervention. This proposal is responsive to the National Institute of Nursing Research and National Institute on Aging PAR-15-348 ?Research on Informal and Formal Caregiving for Alzheimer's Disease? in that we propose to test a technology-based intervention to reduce caregiver burden that, if demonstrated to be effective, can be widely disseminated and ultimately have a significant impact on the stress experienced by AD caregivers and the well-being of people living with Alzheimer's disease.